I asked around the team that was around during Penumbra. The protagonist used to have some backstory, and possibly a name, but it has now been lost to time. It's not 100% certain, but he was probably called Philip in the tech demo times too.

Thanks, I suppose I'll just have to continue calling him "The Protagonist" in order to distinct between the two. One last question if you don't mind, was a name ever considered for the boat at the beginning of Penumbra: Overture, or was it always just "the boat" or "the fishing boat"? Odd question I know, but it's just a small detail that always interested me.

There is no name for the boat as far as our artist from that time remembers - as you only ever see it from the inside. We'll keep in mind in developing the new games that details like these interest some players!

Small details like that are a great addition, but it is true that a name for the boat is a very trivial detail considering how small it is in appearance; I'm probably the only player to wonder if the boat had a name. Thanks for indulging in my silly questions!